Aim. To assess the role of chronic obstructive pulmonary disease (COPD) in the development of unfavorable outcomes of long-term (one-year) prognosis of ST-elevation myocardial infarction (STEMI). Subjects and methods. A total of 529 patients diagnosed with STEMI and no age limits were examined. Group 1 included 65 (12.3%) patients with previously diagnosed COPD; Group 2 consisted of 464 (87.7%) patients without COPD. One-year prognosis was studied in 384 (81.5%) patients. The investigators evaluated the following endpoints: evolving recurrent myocardial infarction (MI), progressive angina pectoris, decompensated chronic heart failure (CHF), repeat percutaneous coronary interventions, stroke, and death. Results. The prevalence of COPD was 12.3% in the patients with STEMI. Unfavorable one-year prognosis was significantly more often registered in the comorbidity group regardless of age, gender, and smoking status. COPD increased the risk of combined endpoints by 1.9 times within a year after MI and that of decompensated CHD by 2.6 times during a year after STEMI. Conclusion. COPD may be an independent risk factor for unfavorable outcomes during a year after MI.